With the improvement of people's living standard and the changing of their lifestyle, cardiovascular diseases have become one main disease, which is not only threatening human health and life, but also influencing medical and financial revenue. There are about 16.5 million persons died from cardiovascular diseases per year on the worldwide. In China, the number of deaths has reached 3 million per year, accounting for 45% of the total death toll.
The clinical applications of the therapeutic methods, such as percutaneous transluminal coronary angioplasty (PTCA), cardiac surgery extracorporeal circulation, coronary artery bypass grafting, rescue and treatment of complex congenital heart diseases, valve replacement and great vessel surgery etc., have saved the lives of cardiovascular patients to a certain degree. However, the occurrence of postoperative ischemia/reperfusion (I/R) damage has become a main challenge for long-term effect of cardiovascular surgery. Besides, I/R damage caused by resuscitation after cardiac arrest, cardiovascular spasm relief and thrombolysis has also influenced on the effect of the rescue and treatment. As a result, the prevention and amelioration of myocardial I/R damage are believed to be an important aspect for improving the effect of rescue and treatment and reducing mortality of the cardiovascular diseases.
In the early stage of the myocardial I/R, the excessively released peroxides and pro-inflammatory factors from the coronary vessel endothelial cells and leukocytes, and over-expressed adhesion molecules and the like results in an adhesion between leukocytes and vascular endothelial cells. Further, those peroxides and proteases, which are released from the leukocytes adhered to vascular endothelial cells, damages the vascular endothelial cells and basement membrane, resulting in a leakage of plasma proteins. All of the edema around blood vessels induced by a leakage of plasma proteins, leukocytes emigrated from vessels, capillary occlusion caused by vascular endothelia swelling or micro-thrombus and the like can lead to the necrosis or apoptosis of peripheral myocardial cells, eventually forming myocardial infarction. Amelioration of the I/R-caused microcirculation disorder is an important aspect for reducing myocardial damage after I/R. As a result, it is extremely urgent to research and develop a medicine for preventing and improving the myocardial I/R damage.
Danshensu, namely, (3,4-dihydroxyphenyl)lactic acid, is a main water-soluble component in Radix Salviae Militiorrhizae (Danshen), a traditional Chinese drug. It has been confirmed in our prior researches that Danshensu had a potential for inhibiting the following: the production of peroxides in rat's mesenteric venule walls caused by I/R, the expression of leucocytes adhesion molecules CD11b/CD18, the adhesion between leucocytes and venule walls, and the leakage of plasma albumin. However, it is still unclear whether Danshensu has an influence on cardiac microcirculation disorder and myocardial damage caused by I/R. Notoginsenoside R1 is one of the main saponins of Panax notoginseng (Sanqi). In our previous researches, it has been verified that notoginsenoside R1 can reduce leukocytes adhered to rat's liver caused by I/R and can ameliorate microcirculation disorder of the liver. As yet, it is not known whether notoginsenoside R1 can act on cardiac microcirculation disorder and myocardial damage caused by I/R.